Patent GB-245854-A (GB)
Title: Improvements in or relating to automatic or semi automatic telephone systems
IPC: H04Q3/42
Filed: 1924-10-17
Abstract: 245,854. Automatic Telephone Manu facturing Co., Ltd., and Passmore, W. O. Oct. 17, 1924. Addition to 230,006. Automatic exchange systems. - In a system employing register-controllers of the code-translating type and having a single distributing frame common to a number of register-controllers as described in the parent Specification, the office registers are switches of standard Strowger type and their wipers are connected up in pairs in succession to a set of relays which determine the value of each translated digit. The setting of these relays is controlled by arbitrary crosswirings at the distributing frame, to a series of bus-bars each differently connected. In the system shown, the bus-bars E, B, EB are connected respectively to earth, battery and to alternative earth and battery. In the following detailed description it will be assumed that the translated routing number corresponding to a dialled code 33 is 19. Setting of register-controller. A calling- subscriber is connected over his line switch LS, Fig. 1, to a trunk group TC and thence over a non-numerical switch RS to an idle registercontroller, Figs. 2 and 4, in which relay 38 operates over the earthed conductor 32 and earths the holding conductor 107. The first two sets of three impulses are repeated by relay 6 over the circuit 10, 31, 44, 56 to the vertical and rotary magnets VM, RM of the office register CS in the usual manner, after which the four numerical digits are similarly repeated to the digit registers DR1 .. DR4. Transmission of translated digits. As soon as the two exchange digits have been registered, wiper 55 of the input control switch ICS in its 3rd position completes a circuit for relay 39 which connects up the translating relays TR1 .. TR4 in pairs and oppositely to the conductors 201, 203. The output control switch OCS in its 1st position connects up wipers a, b of the office register so that, in the present case with contact 61 jumpered to the earthed bar E and with contact 62 disconnected, relay TR1 only is operated over the circuit 80, 46<1>, 201, 250, 70, a, E. Relay TR1 first operates partially to close a locking circuit and then operates fully to disconnect its original circuit at armature 80, and to connect earth over the circuit 73, 138, 52, 91 to the first impulse stop conductor 140 in the bank of the sending switch SEN. Relay TR1 also removes a short-circuit from relay M which now operates over the circuit 58, 48 and connects impulse springs 183 over the circuit 107, 72, 154, 163, 170, 59, 60 to the upper winding of relay J and springs 184 over the circuit 107, 72, 154, 163, 171, 174, 155, 153 to the upper winding of relay N. At the next closure of springs 183 two-step relay J operates partially to prepare a locking circuit and upon the succeeding opening of the springs operates fully and extends the impulsing circuit to stepping magnet SM<1> of the sending switch. In a similar manner springs 184 cause the two-step relay N to extend the second impulsing circuit to the outgoing impulsing conductors 33, 34. Upon the first step of the sending switch relay K operates to remove a short-circuit from the springs 184 so that succeeding operations of the springs transmit impulses to the line relay of the selector S, Fig. 1. After one impulse has been thus transmitted, relay L operates over wiper 181 and the earthed lead 140, places a short-circuit across springs 184 to prevent further impulses, operates magnet SM<2> of switch OCS, unlocks relays TR1, J, N and closes a restoring circuit for the sending switch SEN. When this restoration is complete, relay L releases, switch OCS advances its wipers to the 2nd position in which they connect up wipers c, d, and a new setting of the translating relays TR1 .. TR4 takes place. Since contact 63 is disconnected and contact 64 jumpered to the bar EB, the alternate connection of earth and battery to this bar results in the operation of both relays TR3, TR4 over the circuit 203, 253, 71, 202, and these relays effect the earthing of the ninth impulse stop conductor 148. The transmission of the second routing digit of nine impulses now takes place in a similar manner. Further routing-digits up to a total of six can be similarly provided for by means of wipers e, f of the office register CS and by wipers g .. l of a second similar register CS1. Retransmission of numerical digits; release of register-controller. In the present case after the second routing-digit, relay M is short-circuit'ed over the circuit 164, 150, 94, 91, 52, 138, 73 since none of the translating relays is now energized. Relay M on release completes a circuit 73, 52, 150, 164, 169, 137, 74 for magnet SM<2> which steps the control switch OCS into its 7th position. Relay M now re-energizes since the short-circuit is broken at wiper 73 and if the hundreds digit has been registered, earth is extended from wiper 128 over the circuit 72, 154. 163 to springs 183, 184 as before. The first numerical digit as recorded on register DR1 is now retransmitted under the control of the sending switch SEN after which the remaining numerical digits are similarly retransmitted. When the switch OCS moves into its 11th position, relay 38 releases to restore switches ICS, OCS, CS, DR1, DR4, and wiper 73 completes a circuit 204, 44, 31, for switching relay 8, Fig. 1. Wiper 75 retains earth on the test conductor 32 until the register-controller has been completely restored. Premature release. If the calling subscriber dials the exchange code but does not completely dial the numerical digits, the release of relay 38 completes a circuit 45, 106, 74 for restoring the switch OCS to normal. Cancelling exchange code. If no translated routing-digits are required, the terminals reached by the switches CS, CS1 are all left blank so that none of the relays TR1 .. TR4 operates and after a short interval relay M<1> pulls up and completes a circuit 73, 52, 150, 164, 169. 169<1>. 137, 74 for moving the switch OCS to its 7th position in which the retransmission of the numerical digits commences as before. Call to toll operator; cancelling numerical digits. In this case, the contacts engaged by wipers a .. d are jumpered so as to give a routing-number 78 which directs the call to the toll operator. The contacts engaged by wipers e, f are jumpered to bus-bars EB, E, respectively, so that after the transmission of the two routing- digits, relays TR1, TR2 and TR3 operate and complete a circuit 73, 52, 205, 31 for switching relay 8. Releasing register controller after less than four numerical digits; routing dead number calls to operator. These cases may be dealt with in a similar manner by suitable jumperings at the distributing frame giving rise to particular combinations of the relays TR1 .. TR4. Faults. If either of the springs 183, 184 do not operate properly due to short-circuiting or disconnection, the failure of relays J, N to operate completes an alarm circuit 107, 165, 168 (or 177), 156, 157, AC. Specifications 193,694, 194,427. 194,580. 220,923, and 233,007 are referred to. The Provisional Specification states also that relay arrangements similar to those described in the present and parent Specification may be used to record the numerical digits under the control of a rotary switch which returns to normal after each digit, and refers also to a modification in which the common distributing frame is combined with a common impulse machine comprising a series of interrupters mounted on a common shaft, an additional impulse independent of the frame being connected to the impulse control switches. The numerical-digit registers may be similarly connected to the leads from the common impulse machine.